class Car():
    '''一次模拟汽车的简单尝试'''

    def __init__(self, make, model, year):
        '''初始化描述汽车的属性'''
        self.make = make
        self.model = model
        self.year = year
        self.odometer_reading = 0

    def get_descriptive_name(self):
        '''返回整洁的描述性信息'''
        long_name = str(self.year) + ' ' + self.make + ' ' + self.model
        return long_name.title()

    def read_odometer(self):
        '''打印一条指出汽车里程的信息'''
        print("This car has " + str(self.odometer_reading) + " miles on it. ")

    def update_odometer(self, mileage):
        """
        将里程表读数设置为指定的值
        禁止将里程表读数往回调
        """
        if mileage >= self.odometer_reading:
            self.odometer_reading = mileage
        else:
            print("You can't roll back an olometer!")
    def increment_odometer(self, miles):
        """将里程表读数增加指定的量"""
        if miles >= 0:
            self.odometer_reading += miles
        else:
            print("You can't roll back an olometer!")


class Battery():
    """一次模拟电动汽车电瓶的简单尝试"""

    def __init__(self, battery_size=70):
        """初始化电瓶的属性"""
        self.battery_size = battery_size

    def describe_battery(self):
        """打印一条描述电瓶容量的消息"""
        # 少了个self 类里面一定要添加self
        #print("This car has a " + str(battery_size) + " -kWh battery. ")
        print("This car has a " + str(self.battery_size) + " -kWh battery. ")

    def get_range(self):
        """打印一条描述电瓶续航里程的信息"""
        if self.battery_size == 70:
            range = 240
        elif self.battery_size == 80:
            range = 270

        message = "This car can go approximately " + str(range)
        message += " miles on a full charge. "
        print(message)


class ElectricCar(Car):
    """电动汽车的独特之处"""

    def __init__(self, make, model, year):
        """
        电动汽车的独特之处
        初始化父类的属性
        """
        super().__init__(make, model, year)
        self.battery  = Battery()

#    def describe_battery(self):
#        """打印一条描述电瓶容量的消息"""
#        print("This car has a " + str(self.battery_size) + "-kWh battery.")


#my_tesla = ElectricCar('tesla', 'model s', 2016)
#print(my_tesla.get_descriptive_name())
##my_new_car = Car('audi', 'a4', 2016)
#print(my_new_car.get_descriptive_name())
#my_new_car.odometer_reading = 23

#my_new_car.update_odometer(-1)
#my_new_car.read_odometer()


#my_used_car = Car('subaru', 'outback', 2013)
#print(my_used_car.get_descriptive_name())

#my_used_car.update_odometer(23500)
#my_used_car.read_odometer()

#my_used_car.increment_odometer(100)
#my_used_car.read_odometer()

